1. - Lowest transmitter
distortion
of any transceiver ever tested by QST @ -40 dB. Translated that means that
transmitter distortion is less than .01% or 1 part in ten thousand. (QST
10/83) 2. - Highest peak envelop
power
of any SSB transceiver on the market (below $10,000) @ 225 watts on SSB.
Continuous key down power is 160 to 180 watts.
3. - Because of the high voltage
final
stages and dynamic head room of the power supply, the AM transmit
capability can easily exceed 100% modulation. Properly realigned 102s will
do 110 to 120% on positive modulation peaks without cutoff at the
negative or positive peaks . Therefore, when properly adjusted there
is no splatter distortion. In addition it is capable of HI-FI AM transmit
audio with a frequency response (at 100% modulation) from 45 to 20,000
cycles with no attenuation and exceedingly low distortion. And, that is in
all 102s that are unmodified, just stock.
4. - on SSB transmit audio, as
well as
for AM and FM audio, there is a built in adjustable graphic equalizer
enabling you to independently change your base and treble.

RECEIVER:

1. -
Sensitivity @ 0.12 to 0.145 UV for 10 dB S+N/N thru the wide SSB filter
with the RF amp engaged and peaked. 2.
- MDS on CW typically -140 to -141 dBM thru the standard CW filter and
-142 to -143 dBM thru the narrow CW filter.
3. - Blocking dynamic range with
the RF
amp engaged is -127 dBM. 4. -
Intercept
point of +19 dBM (QST 10/83) 5. -
receiver dynamic exceeds 100 dB.
6. -
synthesizer noise - there is no synthesizer in the VFO of the 102 and
therefore no reciprocal mixing products from it to degrade receiver
performance. 7. - Exceptional
effects
of band pass filters (preselector circuitry) on receiver performance.
Yaesu returned to this "older" technology in the 1000 mp Mark V field as
well as other current top of the line models as there is no other measure
that so effectively reduces second order receiver distortion, effectively
making the receiver brick wall to second order products at better than 130
dB rejection. 8. - High voltage,
high
dynamic range, jfet front end, same as used in the 1000D, 781, 950 and
almost all of the present high end flag ship radios (except for the
$10,000+ radios that have recently come on the market as I am not sure of
their circuitry). As an added note the 102 was the first ham radio to use
this front end (2SK125 in a high voltage [24 volt] doublet Darlington
configuration). 9. - When
properly
aligned the 102 has an audio passband (-6dB points) of 250 to 2950 cycles
on SSB and is the reason that the 102 has the crispest and cleanest audio
of any radio on the market since it has both bass and treble. Listen to
the receive audio of most receivers on SSB and it will sound muffled in
comparison to the 102 (played thru the same speaker). That might not be a
hindrance for the hearing of a 20 or 30 year old, but hams that are 50 and
above will have problems with the lack of high frequency sibilants in
other radios. So, the 102 is easier to copy and less fatiguing to listen
to. In addition there is a treble control for the received audio on the
front panel (not just a treble cut).
10. - The receive section of the 102 was designed by the same
Japanese
fellow who was later called upon by Yaesu to do the receiver in the 1000D.
The front ends and early IF stages are identical in both radios. The first
two IF stages are at the same frequencies and the filters are electrically
interchangeable. The shift and width are the same circuits in both radios
except that the 102 has the two controls ganged for convenience and
flexibility while the 1000D has two separate controls.

REPAIRS:

The newer radios today have their
circuitry and boards based on surface mount double plated thru
configurations where the traces exit one side of a board and appear on the
opposite side. This double plated thru surface mount methodology is almost
impossible to repair economically for the average technician because of
the time and difficulty consumed in tracking down troubles and getting
parts. Therefore the companies frequently resort to changing out boards
instead of actually repairing a circuit. It is not unusual for companies
such as Icom to charge $1200.00 to change out a receiver board in the Icom
756 when it is out of warranty. The same type of charges and way of doing
repairs is currently employed at all the companies. When you are out of
guaranty and take a lightening strike which blows a 10 cent diode it will
cost you $1200 for an entire board to repair that radio or you can buy
another radio. On the other hand the
102 is accessible and repairable with most parts obtained at your local
radio shack for pennies. In addition, I stock every exotic part for the
radio. The user manual/owner's manual
in the 102 describes in detail the function of each and every transistor
and chip in the radio aa well as the "to and from" signal paths. I know of
no other radio that has a user manual or technical or repair manual that
does that so completely. It vastly simplifies repairs for any technician .
Most repair people can handle repairs with a minimum of charge and effort
should they become needed so it won't cost you a down payment on a new car
- more like a tank of gas.

COST:

Depending on accessories, cosmetics, and
whether the radio has been properly repaired and aligned, the average cost
during 2007-8 for a working radio was about $400 to 800 on the open market
unless there are special circumstances such as museum quality cosmetics.
Compare that cost to an Icom 756 pro 2~3 or similar radio. You would save
thousands on the purchase, and low cost for repairs if needed, and have a
radio that would overall run circles around the pro with lower transmitter
distortion, above 100% AM modulation, almost twice the power output and
much better receiver performance characteristics such as blocking dynamic
range at -127 dB, intercept point of +19 dBM. (I am not boasting - check
QST and see the numbers for yourself). In addition the receive audio
passband in the 102 in SSB is 250 to 2950 and is crisper than any other
radio that I have heard. The only other radio that approaches that is the
Icom 781 (not including the current crop of 10,000 radios as I have not
heard them in action). Yes, the new
radios may look nicer but you have to have a manual next to you to operate
the multiple menu stages. On the 102 every control is labeled and what you
see is what you get - so no confusion or accidental changes of the menus
and you have to read the manual to find out how to get back to ground
zero. Clean clear operation, low cost, reliable (well, after I go thru
them), and will overall as a transceiver outperform anything under
$10,000. As far as the transmit section there is nothing that outperforms
the 102 at any price in regard to SSB and AM transmit functions.

ROOFING FILTERS:

I have also researched roofing filters
and in fact the 102 has provision for them in the SSB and CW sections and
these were described in the original factory brochure when the radio was
new. Yaesu saw into the future back in 1983. When those are installed the
receiver performance characteristics are the same as the other 10,000
radios.

DEPRECIATION:

And lastly is depreciation. The resale
value of a 10,000 radio will drop precipitously with time. The value of
the 102 will remain constant or go up.

If you need parts or contact information
check my home page at http://w8kvk.com/nc4l/ or click on HOME
below. 73 de NC4L Mal